Adoptive cell therapy (ACT) is a treatment method in which cells are removed from a donor, cultured and/or manipulated in vitro, and then administered to a patient for the treatment of a disease. A variety of cell types have been used in ACT in an attempt to treat several classes of disorders. For the treatment of cancer, ACT generally involves the transfer of lymphocytes, such as chimeric antigen receptor (CAR) T cells. Use of such CAR T cells involves identifying an antigen on a tumor cell to which a CAR T cell can bind, but tumor heterogeneity can make antigen identification challenging. Accordingly, there remains a need for improved methods for treating cancer using adoptive cell therapy.